Endurance corresponds to the physical resistance to fatigue. Endurance depends on factors such as energy supply, the amount of muscle loaded, or autonomic parameters. Cardiovascular disease substantially reduces endurance.
What is endurance?
Endurance corresponds to physical resistance to fatigue. Physical endurance corresponds to the resistance an organism has to physical fatigue and physical exertion. In a narrower sense, endurance is the motor ability to maintain a certain intensity for a certain period of time without feeling physically severe fatigue or losing the ability to regenerate. Good endurance usually ensures a higher intensity of movements, which allows a more efficient use of energy. In addition to endurance, in many cases athletic techniques and skills, such as the ability to concentrate, help stabilize physical performance. Along with strength, speed, coordination, flexibility and stretching, endurance is one of the most important motor skills. The training of endurance is relevant for every sport. Typical endurance sports include, among others, cross-country skiing, long-distance running, cycling, triathlon, long-distance swimming and rowing. Physical endurance is based on energy supply and depends on factors such as muscle size, muscle contraction type and the motor skills required for a movement. Every person has a certain power limit beyond which the muscles being used can no longer provide the required power. For this reason, endurance performance depends on the very processes that trigger muscle fatigue. In addition to muscle fiber composition, vegetative, psychological, and hormonal aspects are relevant in this context, for example.
Function and task
Endurance, in the sense of physiological resistance to fatigue, depends in large part on processes of energy provision. Depending on the type of energy provision, sports medicine distinguishes aerobic endurance from anaerobic endurance. Aerobic endurance is primarily relevant for long stages and corresponds to the ability to maintain the intensity of the load. In this requirement, the necessary energy is provided mainly by oxidation with oxygen. The measure of aerobic endurance is the specific maximum oxygen uptake. Aerobic endurance training increases the size of the heart muscle. The volume of the heart chamber, the thickness of the heart muscle and the formation of the coronary arteries increase, allowing the heart to expel larger amounts of blood per heartbeat. This simultaneously makes a greater amount of oxygen available in the body, which reaches the muscles through the bloodstream and improves aerobic endurance. Anaerobic endurance, on the other hand, is relevant for shorter periods of intensive exercise. Above a certain load intensity, the muscle is not supplied with sufficient oxygen for aerobic energy production. To ensure that sufficient ATP is still available for muscle work, anti-oxidative processes such as glycolysis take place. As soon as the load stops, the deficit of oxygen is compensated. The oxygen debt variable of anaerobic endurance can be trained. In addition to the type of energy supply, the size of the muscles used plays a role in endurance. A difference in endurance exists between local loads and partial body loads that use about one-sixth of the skeletal muscles, such as arm work in boxing. The type of muscle contraction also has an effect on the endurance required. In this context, a distinction is made between dynamic and static. Each type of endurance must be considered against the background of the respective load. An isolated consideration of one type of endurance is not possible, since the individual types are directly related to each other. The general aerobic endurance takes a key position. It forms the basis for all other endurance types. An equally large correlation as between aerobic and anaerobic endurance exists between endurance types such as strength and speed endurance. Performance-limiting factors include VO2max and thus oxidative processes, muscle fiber composition, buffer capacity, energy supply, respiratory muscles, and thermoregulation including water and electrolyte balance.Equally performance-limiting in terms of endurance can be the coordinative, hormonal, vegetative, psychological and orthopedic parameters.
Diseases and ailments
Endurance is particularly relevant in the context of performance diagnostics. In these examination and testing procedures, the current state of health, resilience, and performance level of athletes are determined. In bicycle ergometry, anaerobic endurance is tested. Similar tests are the Wingate or Katch test which have the patient work at maximum speed for half an hour against greater resistance. Another test from the field of performance diagnostics is treadmill ergometry. Lactate performance tests measure the lactate concentration in the blood, which allows conclusions to be drawn about the individual’s anaerobic threshold. Lactate performance tests are step tests with different performance levels in temporal gradation and primarily determine parameters of the metabolism, such as the anaerobic threshold, the balance between lactate breakdown and lactate release. The Conconi test also determines the anaerobic threshold of the individual, but uses characteristic kinks in the heart rate. Although performance diagnostics is predominantly relevant for training planning and training monitoring within sports medicine, it can also provide indications of diseases. These include primarily cardiovascular diseases, i.e. diseases of the vascular system and diseases of the heart. In this context, in addition to the Conconi test, the cardioergometer test and the Cooper endurance test are also relevant. In the latter, the patient completes a twelve-minute endurance run to determine endurance capacity. The cardioergometer test, on the other hand, corresponds to bicycle ergometry for patients with cardiovascular damage. A specific target pulse rate stops the test and provides results to the physician for analysis.
